I just got in my new 145mph cluster with the white faced guages. I'm going to pull out my 85mph cluster, but while I'm at it I'd like to correct my speedo (I changed from 3.23 rear gears to 3.70). I read the FAQ about this but I still have question.
Would anyone happen to know what gears come in an 87 IROC that originally came with an 85mph speedometer, a 5-spd, and a 3.23 rear end?
I want to try to get away with just changing the driven gear, not the drive gear.
Any help would be greatly appreciated, I really can't wait to bolt these in!

 

For a T5 and 3.70 gears you need a 7 tooth drive gear and a 21 tooth driven gear. I dont know what gears came with T5's and 3.23's. I've been trying to find that out myself for my dad's 3.27 rear end he put in his RS. The closest we can come to is a 7 tooth and an 18 tooth, or a 9 tooth and a 23 tooth. However we cant find an 18 or 23 tooth gear from GM.

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1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
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